Water bottle cap



FIG. 1 is a top-down perspective view of a water bottle cap showing my new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a left elevation view thereof;

FIG. 5 is a right elevation view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof; and,

FIG. 8 is a bottom-up perspective view thereof.

The broken lines are shown for the purpose of illustrating portions of the water bottle cap that form no part of the claimed design. 

CLAIM The ornamental design for a water bottle cap, as shown and described. 